Light travels in ___________ lines from its source, it cannot bend around objects (CURVED or STRAIGHT?)
STRAIGHT
What is the difference between umbra and penumbra?
Umbra: fully shaded region. Penumbra: partially shaded region.
Give two examples of transparent objects.
Materials that allow light to pass through. Ex.: glass and lens.
Give two examples of opaque materials.
Materials that do NOT allow light to pass through. Ex.: wood, metal, thick plastic.
Give two examples of transluncent objects.
Materials that allow SOME light to pass through. Ex.: some types of cloth, stained glass.
The Law of REFLECTION states that, on reflection from a smooth surface, the angle of the reflected ray is ___________ to the angle of the incident ray. (DIFFERENT or EQUAL?)
EQUAL
7) If the light is reflecting at an angle of 30º, what is the angle of incidence?
30º
How is the image of an object in a convex mirror?
Image is upright and smaller that the object
How is the image of an object in a concave mirror?
The position, size, and type of the image depends on how close the object is to the mirror.
Refraction is a change in _______ of light as it travels from one material to another. (DIRECTION or INTENSITY?)
DIRECTION
Which one is a concave lens? Which one is a convex lens?
A. Convex. B. Concave
What is the function of the retina?
The retina is a special lining on the back of the eye which has receptor cells that send messages to the brain.
What is the function of the pupil?
The pupil controls the amount of light entering the eye.
What is the function of the iris?
The iris is a band of muscle which controls the pupil.
